[11/13] mfd: pm8008: rework driver

Rework the pm8008 driver to match the new binding which no longer
describes internal details like interrupts and register offsets
(including which of the two consecutive I2C addresses the registers
belong two).

Instead make the interrupt controller implementation internal and pass
interrupts to the subdrivers using MFD cell resources.

Note that subdrivers may either get their resources, like register block
offsets, from the parent MFD or this can be included in the subdrivers
directly.

In the current implementation, the temperature alarm driver is generic
enough to just get its base address and alarm interrupt from the parent
driver, which already uses this information to implement the interrupt
controller.

The regulator driver, however, needs additional information like parent
supplies and regulator characteristics so in that case it is easier to
just augment its table with the regulator register base addresses.

Similarly, the current GPIO driver already holds the number of pins and
that lookup table can therefore also be extended with register offsets.

Note that subdrivers can now access the two regmaps by name, even if the
primary regmap is registered last so that it's returned by default when
no name is provided in lookups.

Finally, note that the current QPNP GPIO and temperature alarm
subdrivers need some minor rework before they can be used with non-SPMI
devices like the PM8008. The MFD cell names therefore use a "qpnp"
rather than "spmi" prefix to prevent binding until the drivers have been
updated.

Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/mfd/Kconfig                   |  1 +
 drivers/mfd/qcom-pm8008.c             | 95 +++++++++++++++++++++++----
 include/dt-bindings/mfd/qcom-pm8008.h | 19 ------
 3 files changed, 85 insertions(+), 30 deletions(-)
 delete mode 100644 include/dt-bindings/mfd/qcom-pm8008.h

Mon, May 06, 2024 at 05:08:28PM +0200, Johan Hovold kirjoitti:
> Rework the pm8008 driver to match the new binding which no longer
> describes internal details like interrupts and register offsets
> (including which of the two consecutive I2C addresses the registers
> belong two).
> 
> Instead make the interrupt controller implementation internal and pass
> interrupts to the subdrivers using MFD cell resources.
> 
> Note that subdrivers may either get their resources, like register block
> offsets, from the parent MFD or this can be included in the subdrivers
> directly.
> 
> In the current implementation, the temperature alarm driver is generic
> enough to just get its base address and alarm interrupt from the parent
> driver, which already uses this information to implement the interrupt
> controller.
> 
> The regulator driver, however, needs additional information like parent
> supplies and regulator characteristics so in that case it is easier to
> just augment its table with the regulator register base addresses.
> 
> Similarly, the current GPIO driver already holds the number of pins and
> that lookup table can therefore also be extended with register offsets.
> 
> Note that subdrivers can now access the two regmaps by name, even if the
> primary regmap is registered last so that it's returned by default when
> no name is provided in lookups.
> 
> Finally, note that the current QPNP GPIO and temperature alarm
> subdrivers need some minor rework before they can be used with non-SPMI
> devices like the PM8008. The MFD cell names therefore use a "qpnp"
> rather than "spmi" prefix to prevent binding until the drivers have been
> updated.

...

> +static void devm_irq_domain_fwnode_release(void *res)
> +{

> +	struct fwnode_handle *fwnode = res;

Unneeded line, can be

static void devm_irq_domain_fwnode_release(void *fwnode)

> +	irq_domain_free_fwnode(fwnode);
> +}

...

> +	dummy = devm_i2c_new_dummy_device(dev, client->adapter, client->addr + 1);
> +	if (IS_ERR(dummy)) {
> +		rc = PTR_ERR(dummy);
> +		dev_err(&client->dev, "failed to claim second address: %d\n", rc);
> +		return rc;

		return dev_err_probe(...);

> +	}

...

> +	name = devm_kasprintf(dev, GFP_KERNEL, "%pOF-internal", dev->of_node);

You are using fwnode for IRQ domain and IRQ domain core uses fwnode, why OF here?

	name = devm_kasprintf(dev, GFP_KERNEL, "%pfw-internal", dev_fwnode(dev));

> +	if (!name)
> +		return -ENOMEM;
> +
> +	name = strreplace(name, '/', ':');

> +	fwnode = irq_domain_alloc_named_fwnode(name);
> +	if (!fwnode)
> +		return -ENOMEM;

...

> +	rc = devm_regmap_add_irq_chip_fwnode(dev, fwnode, regmap, client->irq,
>  				IRQF_SHARED, 0, &pm8008_irq_chip, &irq_data);
> -		if (rc)
> -			dev_err(dev, "failed to add IRQ chip: %d\n", rc);
> +	if (rc) {
> +		dev_err(dev, "failed to add IRQ chip: %d\n", rc);
> +		return rc;

		return dev_err_probe(...);

>  	}

On 06/05/2024 16:08, Johan Hovold wrote:
> Rework the pm8008 driver to match the new binding which no longer
> describes internal details like interrupts and register offsets
> (including which of the two consecutive I2C addresses the registers
> belong two).
> 
> Instead make the interrupt controller implementation internal and pass
> interrupts to the subdrivers using MFD cell resources.
> 
> Note that subdrivers may either get their resources, like register block
> offsets, from the parent MFD or this can be included in the subdrivers
> directly.
> 
> In the current implementation, the temperature alarm driver is generic
> enough to just get its base address and alarm interrupt from the parent
> driver, which already uses this information to implement the interrupt
> controller.
> 
> The regulator driver, however, needs additional information like parent
> supplies and regulator characteristics so in that case it is easier to
> just augment its table with the regulator register base addresses.
> 
> Similarly, the current GPIO driver already holds the number of pins and
> that lookup table can therefore also be extended with register offsets.
> 
> Note that subdrivers can now access the two regmaps by name, even if the
> primary regmap is registered last so that it's returned by default when
> no name is provided in lookups.
> 
> Finally, note that the current QPNP GPIO and temperature alarm
> subdrivers need some minor rework before they can be used with non-SPMI
> devices like the PM8008. The MFD cell names therefore use a "qpnp"
> rather than "spmi" prefix to prevent binding until the drivers have been
> updated.
> 
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
>   drivers/mfd/Kconfig                   |  1 +
>   drivers/mfd/qcom-pm8008.c             | 95 +++++++++++++++++++++++----
>   include/dt-bindings/mfd/qcom-pm8008.h | 19 ------
>   3 files changed, 85 insertions(+), 30 deletions(-)
>   delete mode 100644 include/dt-bindings/mfd/qcom-pm8008.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 4b023ee229cf..bfcb68c62b07 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -2208,6 +2208,7 @@ config MFD_ACER_A500_EC
>   config MFD_QCOM_PM8008
>   	tristate "QCOM PM8008 Power Management IC"
>   	depends on I2C && OF
> +	select MFD_CORE
>   	select REGMAP_I2C
>   	select REGMAP_IRQ
>   	help
> diff --git a/drivers/mfd/qcom-pm8008.c b/drivers/mfd/qcom-pm8008.c
> index c7a4f8a60cd4..706a725428dd 100644
> --- a/drivers/mfd/qcom-pm8008.c
> +++ b/drivers/mfd/qcom-pm8008.c
> @@ -7,8 +7,10 @@
>   #include <linux/gpio/consumer.h>
>   #include <linux/i2c.h>
>   #include <linux/interrupt.h>
> +#include <linux/ioport.h>
>   #include <linux/irq.h>
>   #include <linux/irqdomain.h>
> +#include <linux/mfd/core.h>
>   #include <linux/module.h>
>   #include <linux/of.h>
>   #include <linux/of_platform.h>
> @@ -16,8 +18,6 @@
>   #include <linux/regmap.h>
>   #include <linux/slab.h>
>   
> -#include <dt-bindings/mfd/qcom-pm8008.h>
> -
>   #define I2C_INTR_STATUS_BASE		0x0550
>   #define INT_RT_STS_OFFSET		0x10
>   #define INT_SET_TYPE_OFFSET		0x11
> @@ -45,6 +45,16 @@ enum {
>   #define PM8008_GPIO1_ADDR	PM8008_PERIPH_2_BASE
>   #define PM8008_GPIO2_ADDR	PM8008_PERIPH_3_BASE
>   
> +/* PM8008 IRQ numbers */
> +#define PM8008_IRQ_MISC_UVLO	0
> +#define PM8008_IRQ_MISC_OVLO	1
> +#define PM8008_IRQ_MISC_OTST2	2
> +#define PM8008_IRQ_MISC_OTST3	3
> +#define PM8008_IRQ_MISC_LDO_OCP	4
> +#define PM8008_IRQ_TEMP_ALARM	5
> +#define PM8008_IRQ_GPIO1	6
> +#define PM8008_IRQ_GPIO2	7
> +
>   enum {
>   	SET_TYPE_INDEX,
>   	POLARITY_HI_INDEX,
> @@ -150,21 +160,65 @@ static const struct regmap_irq_chip pm8008_irq_chip = {
>   	.get_irq_reg		= pm8008_get_irq_reg,
>   };
>   
> -static struct regmap_config qcom_mfd_regmap_cfg = {
> +static const struct regmap_config qcom_mfd_regmap_cfg = {
> +	.name		= "primary",
> +	.reg_bits	= 16,
> +	.val_bits	= 8,
> +	.max_register	= 0xffff,
> +};
> +
> +static const struct regmap_config pm8008_regmap_cfg_2 = {
> +	.name		= "secondary",
>   	.reg_bits	= 16,
>   	.val_bits	= 8,
>   	.max_register	= 0xffff,
>   };
>   
> +static const struct resource pm8008_temp_res[] = {
> +	DEFINE_RES_MEM(PM8008_TEMP_ALARM_ADDR, 0x100),
> +	DEFINE_RES_IRQ(PM8008_IRQ_TEMP_ALARM),
> +};
> +
> +static const struct mfd_cell pm8008_cells[] = {
> +	MFD_CELL_NAME("qcom-pm8008-regulator"),
> +	MFD_CELL_RES("qpnp-temp-alarm", pm8008_temp_res),
> +	MFD_CELL_NAME("qpnp-gpio"),
> +};
> +
> +static void devm_irq_domain_fwnode_release(void *res)
> +{
> +	struct fwnode_handle *fwnode = res;
> +
> +	irq_domain_free_fwnode(fwnode);
> +}
> +
>   static int pm8008_probe(struct i2c_client *client)
>   {
>   	struct regmap_irq_chip_data *irq_data;
> +	struct device *dev = &client->dev;
> +	struct regmap *regmap, *regmap2;
> +	struct fwnode_handle *fwnode;
> +	struct i2c_client *dummy;
>   	struct gpio_desc *reset;
> +	char *name;
>   	int rc;
> -	struct device *dev;
> -	struct regmap *regmap;
>   
> -	dev = &client->dev;
> +	dummy = devm_i2c_new_dummy_device(dev, client->adapter, client->addr + 1);
> +	if (IS_ERR(dummy)) {
> +		rc = PTR_ERR(dummy);
> +		dev_err(&client->dev, "failed to claim second address: %d\n", rc);
> +		return rc;
> +	}
> +
> +	regmap2 = devm_regmap_init_i2c(dummy, &qcom_mfd_regmap_cfg);
> +	if (IS_ERR(regmap2))
> +		return PTR_ERR(regmap2);
> +
> +	rc = regmap_attach_dev(dev, regmap2, &pm8008_regmap_cfg_2);
> +	if (rc)
> +		return rc;
> +
> +	/* Default regmap must be attached last. */
>   	regmap = devm_regmap_init_i2c(client, &qcom_mfd_regmap_cfg);
>   	if (IS_ERR(regmap))
>   		return PTR_ERR(regmap);
> @@ -173,14 +227,33 @@ static int pm8008_probe(struct i2c_client *client)
>   	if (IS_ERR(reset))
>   		return PTR_ERR(reset);
>   
> -	if (of_property_read_bool(dev->of_node, "interrupt-controller")) {
> -		rc = devm_regmap_add_irq_chip(dev, regmap, client->irq,
> +	name = devm_kasprintf(dev, GFP_KERNEL, "%pOF-internal", dev->of_node);
> +	if (!name)
> +		return -ENOMEM;
> +
> +	name = strreplace(name, '/', ':');
> +
> +	fwnode = irq_domain_alloc_named_fwnode(name);
> +	if (!fwnode)
> +		return -ENOMEM;
> +
> +	rc = devm_add_action_or_reset(dev, devm_irq_domain_fwnode_release, fwnode);
> +	if (rc)
> +		return rc;
> +
> +	rc = devm_regmap_add_irq_chip_fwnode(dev, fwnode, regmap, client->irq,
>   				IRQF_SHARED, 0, &pm8008_irq_chip, &irq_data);
> -		if (rc)
> -			dev_err(dev, "failed to add IRQ chip: %d\n", rc);
> +	if (rc) {
> +		dev_err(dev, "failed to add IRQ chip: %d\n", rc);
> +		return rc;
>   	}
>   
> -	return devm_of_platform_populate(dev);
> +	/* Needed by GPIO driver. */
> +	dev_set_drvdata(dev, regmap_irq_get_domain(irq_data));
> +
> +	return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, pm8008_cells,
> +				ARRAY_SIZE(pm8008_cells), NULL, 0,
> +				regmap_irq_get_domain(irq_data));
>   }
>   
>   static const struct of_device_id pm8008_match[] = {
> diff --git a/include/dt-bindings/mfd/qcom-pm8008.h b/include/dt-bindings/mfd/qcom-pm8008.h
> deleted file mode 100644
> index eca9448df228..000000000000
> --- a/include/dt-bindings/mfd/qcom-pm8008.h
> +++ /dev/null
> @@ -1,19 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0-only */
> -/*
> - * Copyright (c) 2021 The Linux Foundation. All rights reserved.
> - */
> -
> -#ifndef __DT_BINDINGS_MFD_QCOM_PM8008_H
> -#define __DT_BINDINGS_MFD_QCOM_PM8008_H
> -
> -/* PM8008 IRQ numbers */
> -#define PM8008_IRQ_MISC_UVLO	0
> -#define PM8008_IRQ_MISC_OVLO	1
> -#define PM8008_IRQ_MISC_OTST2	2
> -#define PM8008_IRQ_MISC_OTST3	3
> -#define PM8008_IRQ_MISC_LDO_OCP	4
> -#define PM8008_IRQ_TEMP_ALARM	5
> -#define PM8008_IRQ_GPIO1	6
> -#define PM8008_IRQ_GPIO2	7
> -
> -#endif

Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

On Mon, May 06, 2024 at 10:18:58PM +0300, Andy Shevchenko wrote:
> Mon, May 06, 2024 at 05:08:28PM +0200, Johan Hovold kirjoitti:

> > +static void devm_irq_domain_fwnode_release(void *res)
> > +{
> 
> > +	struct fwnode_handle *fwnode = res;
> 
> Unneeded line, can be
> 
> static void devm_irq_domain_fwnode_release(void *fwnode)
> 
> > +	irq_domain_free_fwnode(fwnode);
> > +}

I think I prefer it this way for clarity and for type safety in the
unlikely even that the argument to irq_domain_free_fwnode() would ever
change.

> > +	name = devm_kasprintf(dev, GFP_KERNEL, "%pOF-internal", dev->of_node);
> 
> You are using fwnode for IRQ domain and IRQ domain core uses fwnode, why OF here?
> 
> 	name = devm_kasprintf(dev, GFP_KERNEL, "%pfw-internal", dev_fwnode(dev));

This driver only support OF so why bother.

Johan

On Thu, May 9, 2024 at 12:42 PM Johan Hovold <johan@kernel.org> wrote:
> On Mon, May 06, 2024 at 10:18:58PM +0300, Andy Shevchenko wrote:
> > Mon, May 06, 2024 at 05:08:28PM +0200, Johan Hovold kirjoitti:

...

> > > +static void devm_irq_domain_fwnode_release(void *res)
> > > +{
> >
> > > +   struct fwnode_handle *fwnode = res;
> >
> > Unneeded line, can be
> >
> > static void devm_irq_domain_fwnode_release(void *fwnode)
> >
> > > +   irq_domain_free_fwnode(fwnode);
> > > +}
>
> I think I prefer it this way for clarity and for type safety in the
> unlikely even that the argument to irq_domain_free_fwnode() would ever
> change.

If it ever changes, the allocation part most likely would need an
update and since devm_add_action() takes this type of function, I
don't believe the argument would ever change from void * to something
else. With this it just adds an additional burden on the conversion.

> > > +   name = devm_kasprintf(dev, GFP_KERNEL, "%pOF-internal", dev->of_node);
> >
> > You are using fwnode for IRQ domain and IRQ domain core uses fwnode, why OF here?
> >
> >       name = devm_kasprintf(dev, GFP_KERNEL, "%pfw-internal", dev_fwnode(dev));
>
> This driver only support OF so why bother.

Sure, but it makes a bit of inconsistency. Besides that dereferencing
of_node might also add a burden one day we want to get rid of it or
move it somewhere else, or convert to the list_head or so.
dev_of_node(dev) in this case prevents from looking into this case.